Square electromagnetic coil bobbin assembly

ABSTRACT

This invention is intended to improve the electromagnetic coil technology currently used in tattoo machines. Existing coil technology generates electromagnetism that causes a round steel post to alternately repel and attract an armature bar, moving a needle bar and attached needle groupings into and out of the skin in the act of tattooing. The Square Electromagnetic Coil Bobbin Assembly uses a square steel post instead of a round post, increasing the surface area where the post contacts the armature bar and improving the magnetism and general movement of the bar. Increasing the amount of metal-to-metal contact results in significant improvements in the overall functioning of the tattoo machine and the operator&#39;s ability to achieve more solid color, smoother shading, and more consistent lines, all of which depend on the rate of movement of the armature bar. The Square Electromagnetic Coil Bobbin Assembly also uses removable instead of non-removable retaining washers and O-rings for the magnetic wire to allow the operator to customize and repair the magnetic wire.

BACKGROUND OF THE INVENTION

[0001] This invention pertains to the field of tattooing, and isintended to improve the coil technology currently used in tattoomachines.

[0002] The electromagnetic coil assembly is the most important componentof any tattoo machine that uses electromagnetism to operate, and theSquare Electromagnetic Coil Bobbin Assembly is designed to increase theelectromagnetism that is generated. Its design is similar to existingcoil assemblies, but the most important difference is the use of asquare steel post instead of a round steel post, which has been thestandard in coil construction since coils started being used in tattoomachines. Existing coil technology also uses non-removable retainingwashers and O-rings for the magnetic wire, whereas the ones used by theSquare Electromagnetic Coil Bobbin Assembly can be removed to customizeand repair the magnetic wire. FIG. 1 shows a tattoo machine with theSquare Electromagnetic Coil Bobbin Assembly.

BRIEF SUMMARY OF THE INVENTION

[0003] The object of the Square Electromagnetic Coil Bobbin Assembly(shown in FIG. 3) is to improve the performance of current tattoomachines and facilitate the removal and replacement of the retainingwashers and O-rings.

[0004] The Square Electromagnetic Coil Bobbin Assembly improves currentcoil technology by changing the shape of the post from round to square,increasing the surface area where the post contacts the armature bar andimproving the magnetism and general movement of the bar (see FIG. 4).When used with the electromagnetic coil, the armature bar powers aneedle bar and attached needle groupings that move into and out of theskin in the act of tattooing. Increasing the amount of metal-to-metalcontact results in significant improvements in the overall functioningof the tattoo machine and the operator's ability to achieve more solidcolor, smoother shading, and more consistent lines, all of which dependon the rate of movement of the armature bar.

[0005] The Square Electromagnetic Coil Bobbin Assembly also usesretaining washers and O-rings that can be removed, allowing the operatorto customize and repair the magnetic wire without damaging the retainingwasher.

BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING

[0006]FIG. 1 shows the tattoo machine with the Square ElectromagneticCoil Bobbin Assembly.

[0007]FIG. 2 shows the Square Electromagnetic Coil Assembly.

[0008]FIG. 3 shows the Square Electromagnetic Coil Bobbin Assembly indetail.

[0009]FIG. 4 shows the specific area where the square coil posts contactthe armature bar compared to the area where standard round coil postscontact the armature bar.

[0010]FIG. 5 shows how power is supplied to the Square ElectromagneticCoil Bobbin Assembly.

DETAILED DESCRIPTION OF THE INVENTION Components

[0011] The Square Electromagnetic Coil Bobbin Assembly (see FIG. 3)includes the following:

[0012] a square post made of 1018- to 1025-grade steel, where the posthas machined grooves measuring {fraction (1/16)}″ by {fraction (1/16)}″at opposite ends, starting ⅛″ in from each end

[0013] 1 mil. polyimide insulation tape between the steel post and thewire windings

[0014] AWG 22- to AWG 25-gauge magnetic copper wire, as follows:

[0015] if the bobbin is used as the front coil, it may have between 4and 11 layers of wire; if used as the back coil, it may have between 4and 10 layers (must be an even number of layers)

[0016] if the bobbin is used as the front coil, it may have one morelayer of wire than the back coil

[0017] all visible wires must be shrink-wrapped or otherwise insulated

[0018] retaining washers to secure the wire into layers from the top tothe bottom of the post

[0019] if necessary, buna-n O-rings to secure the retaining washers

[0020] any form of tape to cover and protect the exterior of thewindings

[0021] a decal with the company logo may be applied to the tape foraesthetic purposes

Manufacturing and Assembly

[0022] A piece of 1018- to 1025-grade steel stock is machined on a CNCmill according to specifications to form a shape that appearsrectangular when viewed from the side and square when viewed from thetop. Grooves measuring {fraction (1/16)}″ by {fraction (1/16)}″ aremachined completely around the steel post, ⅛ down from the top and ⅛″ upfrom the bottom, so that the grooves appear in the same place on allfour sides of the post. Chamfered edges are machined on the four anglesbetween the machined grooves. A hole is drilled and tapped into thecentre of one end of the post to a penetration depth of between ¼″ and½″ (recommended taps are 8-32 or 6-32).

[0023] A layer of polyimide insulation tape is wrapped completely aroundthe post so that it covers all four sides of the area between themachined grooves, including the chamfered edges.

[0024] Plastic retaining washers measuring approximately 1″ in diameterand {fraction (1/16)}″ in thickness are slid into the grooves at the topand bottom of the post. Three holes are drilled in each of the tworetaining washers: one larger hole in the centre, measuring at least ¼″in diameter; and two other smaller holes close to the outer edge of thewasher and measuring at least {fraction (1/32)}″ in diameter.

[0025] Each retaining washer is secured with a buna-n o-ring measuring{fraction (1/16)}″ in thickness, ⅜″ in outside diameter, and ¼″ ininside diameter. The two O-rings are inserted on top of the retainingwashers under the edges of the machined grooves.

[0026] The steel post with polyimide tape, retaining washers, andO-rings (together referred to as a bobbin) is wound in magnetic copperwire in the area between the retaining washers, much like thread iswound around a bobbin in a sewing machine. The length of the wire willvary depending on the size of the area to be wound, the thickness of thesteel post, and the number of layers to be wound around the post. Ifused as the front bobbin, the coil may have between 4 and 11 layers ofwire, and the back coil may have between 4 and 10 layers (the back coilmust have an even number of layers). The wire starts from the small holenear the inner edge of the retaining washer and winds onto the polyimideinsulation tape in layers from the bottom to the top and then back tothe bottom, and so on until the desired number of layers is reached. Thewire exits through the small hole near the outer edge of the retainingwasher at either end of the post, depending on whether an odd or evennumber of wire layers is used.

[0027] Any form of tape is wrapped around the exterior of the magneticcopper wire to protect it. The ends of the wire will protrude from thesmaller inner and outer holes in the retaining washers. A decal printedwith the company logo is then applied for aesthetic purposes.

Current Flow

[0028] Electrical current is delivered to the Square ElectromagneticCoil Bobbin Assembly from an external power source (either a 110V to220V wall socket), as shown in FIG. 5. Current flows through thefollowing parts on the Square Electromagnetic Coil Bobbin Assembly:

[0029] from the external source through a cord to an adjustable powersupply that is controlled by depressing a foot-switch

[0030] from the power supply to the tattoo machine through a clip cordwire or RCA jack system

[0031] from the lower binding post male connector, which is attached tothe tattoo machine frame by a single threaded bolt, into the femaleconnector

[0032] from the female connector through two wires, one attached to theelectrolytic axial capacitor and the other attached to the back coil

[0033] through the back coil and then to the front coil through the wirethat joins the front and back coils, and simultaneously through theelectrolytic axial capacitor

[0034] out through ending wires, one from the front coil and the otherfrom the electrolytic axial capacitor, which join at the femaleconnector (this female connector attaches to a male connector on theupper binding post assembly, which is not part of the SquareElectromagnetic Coil Bobbin Assembly)

Function

[0035] When current is delivered to a pair of Square ElectromagneticCoil Bobbin Assemblies, it passes through the magnetic copper wire thatwinds around the square steel posts, magnetizing both of the steelposts. Once magnetized, the square posts function as magnets, attractingand repelling the armature bar with the aid of resistance from a pair ofsteel springs. The attracting and repelling of the armature bar resultsin the vertical up-and-down motion of the armature bar (similar to themotion of a sewing machine needle) and the attached needle bar. Theelectrolytic axial capacitor works with the coil assembly to store andrelease the electrical charges that pass through the assembly, smoothingand regulating current flow. Magnetism is strengthened or reduced usingan adjustable electrical power supply.

1. What we claim as our invention is the square electromagnetic coilbobbin assembly as shown in FIG. 3, including the steel posts, retainingwashers, o-rings, insulation tape, windings, and protective tape.